Patients suffering from chronic kidney disease should take vitamin D supplements to improve their mineral intake and prevent complications, according to a study published in the Journal of Bone and Mineral Research. An international team from India and the U.K. investigated whether taking in cholecalciferol – the most widely known form of vitamin D – can improve biomarkers for mineral metabolism in a randomized clinical trial.

For the study, the team recruited 120 patients with chronic kidney disease in India. The participants were between 18 and 70 years old, comprised both men and women, and had less than 20 nanograms per milliliter of vitamin D. They were then randomly grouped in two: One group was assigned to take 300,000 IU of cholecalciferol, while the other, a matching placebo. The participants took their oral doses at the start of the trial and after eight weeks, with researchers regularly measuring serum vitamin D and other minerals.

Those who took cholecalciferol had significantly higher vitamin D levels than those who took a placebo. They also had lower levels of intact parathyroid hormone (iPTH), a hormone that indicates potential calcium deficiency. This was not the case of those in the placebo group, as the researchers observed a rise in iPTH levels after the trial.

The participants in the cholecalciferol treatment group also had lower uric acid levels than those in the placebo group. Elevated levels of uric acid are common among those with chronic kidney disease, indicating an impaired kidney function.

According to the team, the study builds on evidence supporting the use of vitamin D for those with chronic kidney disease. An earlier study published in the journal Ethnicity and Disease concluded that vitamin D is a vital compound for those with chronic kidney disease, particularly for mineral homeostasis. In their report, researchers from the Charles Drew University of Medicine and Science in Los Angeles highlighted that vitamin D is essential for the healthy function of the immune, renal, and cardiovascular systems.

Getting more vitamin D

Vitamin D is called the “sunshine vitamin” on account of it being the only nutrient the body produces after it is exposed to sunlight. But not everyone gets enough: Over half of the world’s population do not get enough sunlight. In the U.S., over 40 percent of the population is considered vitamin D deficient.

A person’s location could play a role in how much vitamin D he is getting. People who live near the equator, for instance, have more vitamin D than those who live farther away. Lifestyle and diet also play important roles. Those who spend more time indoors and eat a Western diet are prone to vitamin D deficiency.

Salmon. The popular fatty fish contains anywhere between 361 to 685 IU per 100 g. When choosing salmon, go for wild-caught as it has up to 1,300 IU per serving.

Herring and other fatty fish. Herring is one of the best dietary sources of vitamin D – a 100 g serving of fresh Atlantic herring has up to 1,628 IU, which is over three times the reference daily intake (RDI). While pickled herring contains 680 IU for the same amount, it also contains a lot of sodium. Other fatty fish like halibut and mackerel are also great sources of vitamin D.

Cod liver oil. Those who don’t like fish could take cod liver oil supplements, which have around 450 IU per teaspoon. It is also a great source of vitamin A and omega-3 fatty acids.

Learn more about the other health benefits of the sunshine vitamin at VitaminD.news.